code:

trigger = {
    is_year = 1550
    NOT = { is_year = 1650 }
    NED = {
        exists = yes
        ai = yes
        was_player = no
    }
    owner = {
        NOT = { tag = NED }
    }
    region = low_countries_region
    OR = {
        culture = dutch
        culture = flemish
        is_core = NED
    }
    OR = {
        NOT = { has_province_flag = dutch_revolt }
        had_province_flag = { flag = dutch_revolt days = 1825 }
    }
    owner = {
        OR = {
            capital_scope = {
                NOT = { region = low_countries_region }
            }
            NOT = {
                OR = {
                    primary_culture = dutch
                    primary_culture = flemish
                }
            }
        }
    }
}